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<h1>Gallium selenide, GaSe</h1>

Gallium selenide (GaSe) is a layered II-VI semiconductor material with a direct band gap that varies between 2.1 to 2.9 eV depending on the layer thickness. This material has gained considerable attention for its nonlinear optical properties, making it suitable for frequency conversion applications, such as second harmonic generation and parametric oscillation. Due to its layered structure, GaSe can be easily exfoliated, facilitating its use in van der Waals heterostructures with other 2D materials. In its monolayer form, GaSe exhibits strong light-matter interactions, making it a candidate for optoelectronic applications like photodetectors and solar cells. Gallium selenide is also studied for its potential in high-speed transistors and photonic devices, particularly in the ultraviolet and visible spectral regions.

<h2>Other names</h2>
<ul>
<li>Gallium(II) selenide</li>
<li>Gallium monoselenide</li>
</ul>

<h2>External links</h2>
<ul>
<li><a href="https://en.wikipedia.org/wiki/Gallium(II)_selenide">Gallium(II) selenide - Wikipedia</a></li>
<li><a href="https://www.webelements.com/compounds/gallium/gallium_selenide.html">Gallium selenide - WebElements</a></li>
<li><a href="https://pubchem.ncbi.nlm.nih.gov/compound/Gallium-selenide-_GaSe">Gallium selenide (GaSe) - PubChem</a></li>
</ul>
